# a="ping-zhu"
# b="hi"
# print("play pingpong: {}*********{}".format(a, b))
# a = "ping-zhu"
# b = "merry"
# q="play pingpong: {0}, {1}, {0}, {1}".format(a, b)
# print(q)


# a = "ping-zhu"
# b = "pong-chirsmas"
# print("play pingpong: {a}, {b}, {a}, {b}".format(a='ping-33333', b='pong'))
#play pingpong: ping, pong, ping, pong
a = "zhu"
b = "merry"
print(f"playing pingpong: {a}, {b}")